Formation of Cobalt Phosphide Nanodisks as a Bifunctional Electrocatalyst for Enhanced Water Splitting
Exploring efficient and cheap electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is crucial for water splitting. Herein, a novel porous disk-like nanostructured CoP (CoP ND) was synthesized by a facile strategy involving precipitation, ammonia-etching and phosphidation steps. Endowed with abundant catalytic active sites and enriched nanoporosity, CoP ND shows excellent bifunctional catalytic performances toward both HER and OER, which is comparable and even superior to the recently reported noble-metal-free electrocatalysts. Consequently, an efficent water electrolyzer composed of two symmetrical CoP ND electrodes can afford a current density of 10 mA cm–2 at a cell voltage of 1.62 V.